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SyngnathidaeSyngnathidaeSeahorses, Sea Dragons & PipefishSeahorses, Sea Dragons & Pipefish
by Christy Cusickby Christy Cusick
http://www.seahorses.de/gallery.htm
• 35 known species of 35 known species of seahorseseahorse
• Size ranges from Size ranges from 1/4”-14”1/4”-14”• Lifespan 3-7 yearsLifespan 3-7 years• Live in seagrass Live in seagrass
beds and mangrove beds and mangrove rootsroots
• Feed on planktonFeed on plankton• Ambush predatorsAmbush predators 360 brine shrimp/ 360 brine shrimp/
hourhour
http://www.seahorse.org/gallery/Hingens/ingens1Lg
http://www.hkdivephoto.com/stephenwong/seahorse/show009.shtml
Seahorse AnatomySeahorse Anatomy
• Coronet – human Coronet – human fingerprintfingerprint
• Dorsal fin – propulsionDorsal fin – propulsion• Pectoral fins – steeringPectoral fins – steering• Eyes – move independentlyEyes – move independently• Hinged interlocking bony Hinged interlocking bony
platesplates• Gills – behind the headGills – behind the head• Swim bladder Swim bladder
http://www.pbs.org/wgbh/nova/seahorse/basics.html
Seahorse ReproductionSeahorse Reproduction• MonogamousMonogamous• Extensive courtship Extensive courtship
ritualritual• Female releases eggs Female releases eggs
into male brood pouchinto male brood pouch• Male fertilizes eggsMale fertilizes eggs• Pregnant 2-8 weeksPregnant 2-8 weeks• Male gives birthMale gives birth• Why sex-role reversal?Why sex-role reversal?
http://www.colszoo.org/animalareas/shores/seahrse.html
http://www.pbs.org/wgbh/nova/seahorse/roundup.html
Seahorse ConservationSeahorse Conservation
• Lack of dataLack of data• 20 million/year20 million/year• 25-70% decline 25-70% decline
over last 5-10 over last 5-10 yearsyears
• Habitat destructionHabitat destruction
Hippocampus capensisHippocampus capensis Knysna Seahorse Knysna Seahorse
http://www.reefkeeping.com/issues/2004-11/hcs3/
• Souvenirs, trawling Souvenirs, trawling by-catch, aquarium by-catch, aquarium trade trade
• Asian markets Asian markets consume 16 million consume 16 million annuallyannually
• Cure for impotency, Cure for impotency, lowers cholesterol, lowers cholesterol, delicacy in cookingdelicacy in cooking
http://zubi.merseine.nu/student/broschi/Pictures/Zubi/Gefaehrdung/Seeperdchentrocken.jpg
Leafy SeadragonLeafy Seadragon
• Endemic to Endemic to Southern coast of Southern coast of AustraliaAustralia
• Coastal kelp forestsCoastal kelp forests• 1 dorsal fin1 dorsal fin• 2 pectoral fins2 pectoral fins• Leafy appendages Leafy appendages http://www.divegallery.com/Leafy_Sea_Dragon_7.htm
• Body covered with jointed bony platesBody covered with jointed bony plates• 14”- 20” in length14”- 20” in length• Lifespan 5-7 yearsLifespan 5-7 years• Feed on plankton – preferably sea liceFeed on plankton – preferably sea lice
http://www.divetheblue.net/images/354o.jpg?PHPSESSID=d76be6141afc9fb718d7f0b762cb541e
• Can change Can change color to match color to match environmentenvironment
• Always return to Always return to the same spotthe same spot
• Easy for Easy for poachers to findpoachers to find
• No “natural” No “natural” predatorspredators
http://www.divegallery.com/Leafy_Sea_Dragon.htm
Leafy Seadragon ReproductionLeafy Seadragon Reproduction
• Female lays Female lays eggs under eggs under tail of maletail of male
• Brood patch Brood patch 100-250 100-250 eggseggs
• Males carry Males carry from 4-6 from 4-6 weeksweeks
http://www.seaphotos.com/seahorses.html
http://www.seaphotos.com/seahorses.html
• No parental care afterNo parental care after birthbirth
• Hatchlings being to Hatchlings being to feed 3 days after birthfeed 3 days after birth
Weedy SeadragonWeedy Seadragon• Endemic to the Australian coastEndemic to the Australian coast• Lifespan 7-10 yearsLifespan 7-10 years• Up to 18” in lengthUp to 18” in length
http://www.divegallery.com/Weedy_Sea_Dragon.htm
Phyllopteryx taeniolatusPhyllopteryx taeniolatus
http://www.seaphotos.com/seahorses.html
• Males carry Males carry
100-300 eggs 100-300 eggs
http://www.amonline.net.au/fishes/students/focus/seadrag.htm
Seadragon ConservationSeadragon Conservation
• Environment Protection and Biodiversity Environment Protection and Biodiversity Conservation Act 1999Conservation Act 1999
• Aquarium in Western Australia is one of only Aquarium in Western Australia is one of only three aquaria in the world to have legally and three aquaria in the world to have legally and successfully kept leafy sea-dragons on successfully kept leafy sea-dragons on displaydisplay
http://www.oceanwideimages.com
• U.S. imports over U.S. imports over 200,000 seahorses 200,000 seahorses every yearevery year
• By-catch kills By-catch kills millions of species millions of species every yearevery year
• Conservation Conservation programs in Asiaprograms in Asia
http://www.underwater.com.au/image.php/id/1342
ConservationConservation
http://www.pbs.org/wgbh/nova/seahorse/roundup.html
Questions to think aboutQuestions to think about
• What makes them so susceptible to over What makes them so susceptible to over fishing?fishing?
• Low reproductive rateLow reproductive rate• Low success rate of hatchlingsLow success rate of hatchlings• Easy to catch Easy to catch • High demandHigh demand
• What are the benefits of sex-role reversal?What are the benefits of sex-role reversal?• Females can devote more of their energy to producing Females can devote more of their energy to producing
expensive eggs.expensive eggs.
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